Because BC=8㎝

Solution: Let △CPQ∽△CBA after x seconds, and get.

Because △CPQ∽△CBA

So PC:BC=QC:AC

So (8-2x): 8 = x: 6.

The solution is X=2.4.

2. According to Pythagorean theorem, Ba: AC: BC = 5: 3: 4.

Because BC=8㎝

Solution: Let △CPQ∽△CAB after x seconds, and get

Because △CPQ∽△ cab

So PC:CA=QC:BC

So (8-2x): 6 = x: 8.

The solution is X=32/ 1 1.